Preheat the broiler and line a baking sheet with foil. Combine the turkey, breadcrumbs, egg, 1/2 cup cilantro, grated onion, 2 teaspoons ginger and 1/2 teaspoon salt in a large bowl. Mix with your hands until just combined. Form into 20 meatballs (about 1 1/2 inches each); transfer to the prepared baking sheet. Set aside.
Heat the olive oil in a large skillet over medium-high heat. Add the chopped onion, bell pepper and a pinch of salt. Cook, stirring occasionally, until the vegetables are lightly browned and tender, about 5 minutes. Add the remaining 1 teaspoon ginger and the curry powder. Cook, stirring to coat, 1 minute. Add the tomatoes, 1 1/2 cups water and 1/4 teaspoon salt; bring to a simmer. Reduce the heat to low and cook until slightly thickened, about 3 minutes.
Meanwhile, broil the meatballs until lightly browned and just cooked through, about 5 minutes. Nestle the meatballs in the sauce. Cover and cook until the sauce is thickened, 7 minutes. Stir in half of the remaining cilantro; season with salt. Serve the meatballs and sauce with the rice; top with the remaining cilantro.